$(x - 1)^{2000}$ = $(x - 1)^{2020}$
$(x - 1)^{2020}$ - $(x - 1)^{2000}$ = 0
$(x - 1)^{2000}$ . $(x - 1)^{20}$ - $(x - 1)^{2000}$ = 0
$(x - 1)^{2000}$ . ( $(x - 1)^{20}$ - 1) = 0
=> $(x - 1)^{2000}$ = 0 hoặc $(x - 1)^{20}$ - 1 = 0
Nếu $(x - 1)^{2000}$ = 0
$(x - 1)^{2000}$ = $0^{2000}$
x - 1 = 0
x = 0 + 1
x = 1
Nếu $(x - 1)^{20}$ - 1 = 0
$(x - 1)^{20}$ = 0 + 1
$(x - 1)^{20}$ = 1
$(x - 1)^{20}$ = $1^{20}$
x - 1 = 1
x = 1 + 1
x = 2
Vậy x = 1 hoặc 2
